The museum houses a rebuilt Mark 2 Colossus computer alongside an exhibition of the most complex code cracking activities performed at the Park, along with examples of machines continuing the history of the development of computing from the 1940s to the present day. The museum has a policy of having as many of the exhibits as possible in full working order.

Although located on the Bletchley Park 'campus', The National Museum of Computing is an entirely separate charity with its own fund raising and separate entrance/ticketing. TNMOC receives no public funding and relies on the generosity of donors and supporters.

The museum is working with four other organisations, in a group called Qufaro, to create the
National College of Cyber Security for students between 16 and 19 years of age. To open in 2018, the school will be located in Block G which was being renovated in 2017, funded by the Bletchley Park Science and Innovation Centre. (Bletchley Park Trust has no involvement with the college.) [2]

There is also a suite which includes many BBC Micro personal computers which are used to encourage programming among visitors, an area dedicated to women in computer science, and a hands on display of video game consoles from different eras. All of this is alongside various other displays of devices and information regarding the evolution of computing from the 60s to the modern era.

Demonstrations and talks usually occur on the hour when the galleries are open, with slight deviation depending on the number of visitors.

The rest of the museum is open to the public every Thursday, Saturday and Sunday afternoons and most bank holidays, and by appointment for groups only at other times. There are guided tours on Tuesday afternoons, Thursday mornings and other times. There is a modest admission charge to the museum to help cover overheads (including rent).

The museum conducted a crowdfunding campaign in March 2018 to raise funds to build a new gallery for the Turing-Welchman Bombe.[8] The campaign raised over £43,000 via crowd-funding and an additional £20,000 via direct donations.

The museum is managed by the Codes and Ciphers Heritage Trust, a registered charity,[9] with employed and volunteer staff. The title The National Museum of Computing is an operating name.